1. Field of the Invention
The present invention relates to a fastening cap for fastening a plug cord to a wiring terminal inside the engine compartment of an automobile and the like.
2. Prior Art
In engines of automobiles, etc., the distributor and spark plugs are connected by way of connecting plug cords to a plurality of wiring terminals of the distributor cap. When connecting caps are attached to the plug cord terminals and these connecting caps are fastened to the wiring terminals of such a distributor cap, this fastening is ordinarily accomplished by fastening caps that are provided as original parts. FIGS. 7 and 8 show one type of a fastening cap provided as an original part. FIG. 7 is a perspective view of the fastening cap, and FIG. 8 is its bottom view.
As seen from FIGS. 7 and 8, this fastening cap 50 is formed substantially in the shape of a conical tube so that a connecting cap that is at the end of the plug cord can be engaged with the inside thereof. The fastening cap 50 is comprised of a head portion 51 and a skirt portion 52. The skirt portion 52 continuously extends from the lower end of the head portion 51. An engaging opening 53 and an engaging groove 54 which are detachably engaged with engaging protrusions of the tubular wall of a wiring terminal are formed in the skirt portion 52 of the fastening cap 50. The skirt portion 52 of the fasting cap 50 is further provided with a cord lead-out opening 55 which allows the plug cord to be led out from the circumferential surface of the fastening cap 50.
The cord lead-out opening 55 is formed by cutting out a part of the skirt portion 52 so that the opening 55 matches the external diameter of the plug cord. A recess 56 is formed in the head portion 51 of the fastening cap 50. The recess 56 accommodates the projection formed on the head portion of the connecting cap.
Generally, in fastening caps provided as original parts, the cord lead-out opening is formed so as to match the external diameter of the plug cord. As a result, the movement of the connecting cap is restricted; and in cases where the plug cord is to be led out in desired direction, it is necessary to prepare a new fastening cap that has the engaging opening and engaging groove altered in position in accordance with direction in which the cord is led out of the fastening cap. As a result, a new mold is required for manufacturing such a new fastening cap, and this increases the manufacturing cost of the fastening caps.
Accordingly, the inventors conducted a diligent research for a fastening cap for repair use that is inexpensive and has all-purpose utilities. The inventors discovered that with a cord lead-out opening formed by cutting away approximately one-half of the skirt portion in the circumferential direction, cord lead-out can be handled over a broad angular range (as large as 180xc2x0) and the all-purpose utilities of the fastening cap are improved, and this can be done without altering the positions of the engaging opening and engaging groove of the fastening cap. Furthermore, the head portion of the fastening cap is formed so as to have a certain predetermined thickness, and a recess, into which the projection of the head portion of the connecting cap is inserted, is formed in the head portion of the fastening cap that has such a thickness, and the depth of this recess is set to be the same dimension as the height of the projection. With this structure of the fastening cap, it is possible to remove the connecting cap easily.
There are no particular restrictions on the material of the fastening cap. By forming the fastening cap integrally in a single body from synthetic resin, the fastening cap can be easily and inexpensively manufactured. In forming the fastening cap, an injection molding is most preferably used.